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361.
Study of size and mass distribution of particulate matter due to crop residue burning with seasonal variation in rural area of Punjab, India 总被引:1,自引:0,他引:1
Awasthi A Agarwal R Mittal SK Singh N Singh K Gupta PK 《Journal of environmental monitoring : JEM》2011,13(4):1073-1081
Emission from field burning of agricultural crop residue is a common environmental hazard observed in northern India. It has a significant potential health risk for the rural population due to respirable suspended particulate matter (RSPM). A study on eight stage size segregated mass distribution of RSPM was done for 2 wheat and 3 rice crop seasons. The study was undertaken at rural and agricultural sites of Patiala (India) where the RSPM levels remained close to the National Ambient Air quality standards (NAAQS). Fine particulate matter (PM(2.5)) contributed almost 55% to 64% of the RSPM, showing that, in general, the smaller particles dominated during the whole study period with more contribution during the rice crop as compared to that of wheat crop residue burning. Fine particulate matter content in the total RSPM increased with decrease in temperature. Concentration levels of PM(10) and PM(2.5) were higher during the winter months as compared to that in the summer months. Background concentration levels of PM(10), PM(2.5) and PM(10-2.5) were found to be around 97 ± 21, 57 ± 15 and 40 ± 6 μg m(-3), respectively. The levels increased up to 66, 78 and 71% during rice season and 51, 43 and 61% during wheat crop residue burning, respectively. Extensive statistical analysis of the data was done by using pair t-test. Overall results show that the concentration levels of different size particulate matter are greatly affected by agricultural crop residue burning but the total distribution of the particulate matter remains almost constant. 相似文献
362.
Ningombam Linthoingambi Devi Ishwar Chandra Yadav Q. I. Shihua Surendra Singh S. L. Belagali 《Environmental monitoring and assessment》2011,177(1-4):23-33
Pulp and paper mills generate varieties of pollutants depending upon type of the pulping process being used. This paper presents the characteristics of wastewater from South India Paper Mill, Karnataka, India which is using recycled waste paper as a raw material. The raw wastewater consists of 80?C90 mg L???1 suspended solid and 1,010?C1,015 mg L???1 dissolved solid. However, pH varied from 5.5?C6.8. The biochemical oxygen demand and chemical oxygen demand ranged from 200?C210 and 1,120?C1,160 mg L???1, respectively. Aerobic treatment of raw effluent attribute to significant reduction in suspended solid (range between 25 to 30 mg L???1) and total dissolved solid (range between 360 to 390 mg L???1). However, pH, temperature, and electrical conductivity were found superior after treatment. Copper, cadmium, iron, lead, nickel, and zinc were found in less quantity in raw effluent and were almost completely removed after treatment. The dendrogram of the effluent quality parameters clearly indicate that South India Paper Mill does not meet Minimal National Standard set by central Pollution Control Board to discharge in agricultural field. 相似文献
363.
Elderly women of a particular socioecological system are considered to be “living encyclopedias” in biocultural knowledge systems. These women play a pivotal role in retaining and passing on biodiversity-related traditional knowledge to the next generations. Unfortunately the fast changing sociocultural values and the impact of modernity have rendered their knowledge somewhat less valuable and they are being treated as “cultural refugia.” Our study on the importance of these women in the conservation of indigenous biodiversity was conducted in 14 randomly selected villages dominated by the Adi tribe of East Siang District, Arunachal Pradesh (northeast India). Data were collected from 531 women (381 elderly and 150 young to middle aged) during 2003–2008 using conventional social science methods and participatory rural appraisal. One innovative method, namely “recipe contest,” was devised to mobilize Adi women of each village in order to energies them and explore their knowledge relating to traditional foods, ethnomedicines, and conservation of indigenous biodiversity. Results indicated that 55 plant species are being used by elderly Adi women in their food systems, while 34 plant species are integral parts of ethnomedicinal practices. These women identified different plant species found under multistory canopies of community forests. Elderly women were particularly skilled in preparing traditional foods including beverages and held significantly greater knowledge of indigenous plants than younger women. Lifelong experiences and cultural diversity were found to influence the significance of biodiversity use and conservation. The conservation of biodiversity occurs in three different habitats: jhum lands (shifting cultivation), Morang forest (community managed forests), and home gardens. The knowledge and practice of elderly women about habitats and multistory vegetations, regenerative techniques, selective harvesting, and cultivation practices contribute significantly to food and livelihood security while sustaining an array of threatened plant species. Basically, knowledge of elderly women on using biodiversity in food and medicinal systems was found in three categories namely: “individual,” “community,” and “refined.” We identified a need to develop holistic policies to recognize and integrate knowledge and practices of elderly women with local level of planning on sustainable conservation of biodiversity as well as community-based adaptations. 相似文献
364.
Operational Evapotranspiration Mapping Using Remote Sensing and Weather Datasets: A New Parameterization for the SSEB Approach 总被引:1,自引:0,他引:1
Gabriel B. Senay Stefanie Bohms Ramesh K. Singh Prasanna H. Gowda Naga M. Velpuri Henok Alemu James P. Verdin 《Journal of the American Water Resources Association》2013,49(3):577-591
The increasing availability of multi‐scale remotely sensed data and global weather datasets is allowing the estimation of evapotranspiration (ET) at multiple scales. We present a simple but robust method that uses remotely sensed thermal data and model‐assimilated weather fields to produce ET for the contiguous United States (CONUS) at monthly and seasonal time scales. The method is based on the Simplified Surface Energy Balance (SSEB) model, which is now parameterized for operational applications, renamed as SSEBop. The innovative aspect of the SSEBop is that it uses predefined boundary conditions that are unique to each pixel for the “hot” and “cold” reference conditions. The SSEBop model was used for computing ET for 12 years (2000‐2011) using the MODIS and Global Data Assimilation System (GDAS) data streams. SSEBop ET results compared reasonably well with monthly eddy covariance ET data explaining 64% of the observed variability across diverse ecosystems in the CONUS during 2005. Twelve annual ET anomalies (2000‐2011) depicted the spatial extent and severity of the commonly known drought years in the CONUS. More research is required to improve the representation of the predefined boundary conditions in complex terrain at small spatial scales. SSEBop model was found to be a promising approach to conduct water use studies in the CONUS, with a similar opportunity in other parts of the world. The approach can also be applied with other thermal sensors such as Landsat. 相似文献
365.
Sungwon Kim Vijay P. Singh 《Journal of the American Water Resources Association》2013,49(6):1421-1435
Various neural networks models are developed and applied for flood forecasting at Sangye station (no. 1) of the Bocheong Stream catchment, which is one of the International Hydrological Program's representative catchments, Republic of Korea. The neural networks models (NNMs) are multilayer perceptron‐neural networks model (MLP‐NNM), generalized regression neural networks model (GRNNM), and Kohonen self‐organizing feature maps neural networks model (KSOFM‐NNM). Data used for model training and testing are divided into two groups: such as floods and typhoon events. Single conventional application and class segregation implementation are applied to evaluate the neural networks models. KSOFM‐NNM forecasts flood discharge more accurately than do MLP‐NNM and GRNNM for the testing data of Methods I and II for single conventional application and class segregation implementation. This study shows that class segregation can capture the dynamics of different physical processes and overcome the difficulties using single conventional application of neural networks models. 相似文献
366.
A field study made with rice at the Indian Agricultural Research Institute, New Delhi, showed that coating urea with neem
oil, neem cake or neem oil microemulsion improved rice growth and resulted in more grain and straw than did commercial prilled
urea.
Received: 12 April 1999 / Accepted in revised form: 6 August 1999 相似文献
367.
p-Aminodiphenylamine (p-ADPA) has got a binding capacity with tissue proteins. Aspartic and glutamic acids are presumably the responsible units in the protein chain involved in this binding with p-ADPA. p-ADPA is changed into a quinone structure after atmospheric oxidation in Krebs-Ringer-Bicarbonate buffer, pH 7.4 in the presence of trace metal ions. This oxidised form of p-ADPA binds with aspartic acid at pH 7.4 and temperature 40° in 2 hrs. The derivative thus formed absorbs at 450 nm instead of 430 nm. 相似文献
368.
369.
Developing countries situated mostly in latitudes that are projected for the highest climate change impact in the twenty-first century will also have a predictable increase in demand on energy sources. India presents us with a unique opportunity to study this phenomenon in a large developing country. This study finds that climate adaptation policies of India should consider the significance of air conditioners (A/Cs) in mitigation of human vulnerability due to unpredictable weather events such as heat waves. However, the energy demand due to air conditioning usage alone will be in the range of an extra ~750,000 GWh to ~1,350,000 GWh with a 3.7 °C increase in surface temperatures under different population scenarios and increasing incomes by the year 2100. We project that residential A/C usage by 2100 will result in CO2 emissions of 592 Tg to 1064 Tg. This is significant given that India's total contribution to global CO2 emissions in 2009 was measured at 1670 Tg and country's residential and commercial electricity consumption in 2007 was estimated at 145,000 GWh. 相似文献
370.
Polyphenols and polyphenol-rich fractions of plants have been reported to have protective effects against lipid peroxidation,
most probably by serving as scavengers of free radicals and/or by chelating metal ions. In the present study, the effect of
different extracts/subfractions of Chickrassy (Chukrasia tabularis) on peroxyl radical mediated damage to the polyunsaturated fatty acids was investigated. Liver homogenate was used as experimental
material. The production of malondialdehyde served as a marker of lipid peroxidation and oxidative stress. It was observed
that polyphenol-rich fractions, particularly the ethyl acetate fractions of bark and leaves, showed the highest protective
activity of 83.02% and 88.62% inhibition, respectively. This study will help in knowing the scientific validation of this
plant, for its use in ayurvedic formulations.
The current in vitro experiments performed herewith comply with the current laws of India. 相似文献